Kvass is great, a Russian cafe here used to have it off-menu (sadly they closed). I've seen a local producer selling beet kvass but IMO the bread-based one tastes better.
I learned about it last year from the Life of Boris Youtube channel [1], then from my buddy who was making some in his kitchen during lockdown. I started running that spring, and I made gallons of the stuff to drink after runs.
I've had two commercial versions, one from Ochakovskiy, which is more like pop, and one more authentic one which was incredibly funky. I would like to try more versions and recipes, including the archaic "white Kvass" [2]. In fact the white kvass link was what I was planning on posting originally, but it lacks much detail.
If you're curious, there is bottled Kvass in Russian grocery stores. Probably Cinderella bakery in San Francisco has the real kvass - you have to call though. My grandma used to make it out of the rye bread. And if you're curious, in Soviet Union fresh kvass was all over the place.
I've never found a canned/bottled kvass at a "pan-East-European" grocery that was better than "just OK." Usually too sweet, too malty, and too syrupy. Sometimes you see on the cans drying drips of molasses (or motor oil or whatever) that it's sweetened with.
I'd kill for a Soviet street-vendor style kvass: dry, golden-yellow, fizzy, and tasting of burnt toast.
Tons of words in Russian cluster around the same root: "to pickle" is "kvasit" (also, figuratively, "to chug"), leading to related words for sauerkraut and fermented dairy products, "sourdough starter" is "zakvaska," the vessel for fermenting dough is "kvashnia," etc.
> The wide availability and consumption of kvass, including by children of all ages, together with the lacking indication of ABV for kvass on the labels and in advertisements has been named a possible contributor to chronic alcoholism in the former Soviet Union.
Alcoholism comes from the unfulfilled need for camraderie and general dissasfaction with life, not a childhood exposure to a sweet effervescent drink even if it has some alcohol content. It is also a highly seasonal drink, consumed mostly in late spring and summer.
